Organic carrier molecules with anticipated affinity for melanotic tissues will be structurally modified to facilitate bonding and in vivo transport of radioiodine, Tc-99m, and Pt-195m in expectation of scintigraphic localization of occult ocular melanomas. Carrier species will include 7-halo-4-substituted quinolines and furocoumarins (psoralens). In addition, to take advantage of the demonstrated presence of estrogen receptors in certain malignant melanomas, D-ring modified estrogens will be syntesized for complexation with Tc-99m and/or Pt-195m. Labeled compounds will be screened in a transplantable hamster melanoma for tumor and organ biodistribution and pharmacokinetics. A preliminary in vitro evaluation will be performed by melanin binding assays in an attempt to correlate in vitro measurements with in vivo melanoma specificity.